How pandemic helps us to understand Charles Darwin's ideas

Torbay Weekly

As we hear about new variants of the coronavirus, how many people know what this actually means?

This 21st century problem goes back to 1859 and Charles Darwin.

We’re seeing Darwin’s theory of 'natural selection' on fast forward even though viruses were unknown to Charles Darwin himself.

There is even a Torquay connection. Darwin finished the last section of 'The Origin of the Species' while staying at Hesketh Crescent.

What did Darwin propose?

He did not invent the theory of evolution which can be traced back to the ancient Greeks.

He proposed the way that evolution could take place.

His ideas came from careful observation and two essays he had read.

One pointed out that most species increased with every generation. Two parents often had many young.

The other essay showed that most populations stay fairly stable. This meant, he concluded, that there must be a constant competitive struggle for survival.

He never used the expression 'survival of the fittest' but this is how his theory has been summed up.

Darwin also knew that every generation of animals is slightly different.

Breeders had exploited these changes for years. By noticing slight random differences in horses, of example, it was possible to breed a racehorse or a cart horse.

He called this 'artificial selection'. Does nature, he asked, also 'select' the strongest through random changes, a process he called 'natural selection'.

He then proposed that in every generation there are random changes.

These are pure chance and most either have no effect or are dangerous to the animal but occasionally a random change gives the offspring an advantage.

A giraffe which, by pure chance, had a longer neck was able to reach leaves which were too high for other giraffes.

We now have a scientific explanation for these changes.

Characteristics are inherited though DNA and the DNA molecule is subject to random 'mistakes', we now call mutations or variations.

If the 'mistake' gives the offspring an advantage it will survive and breed.

Evolution by natural selection in animals takes place over many years but because viruses spread very rapidly, they mutate rapidly.

There are thousands of mutations all the time but if one has an advantage it will soon become dominant.

The delta variant became dominant as it was more 'sticky' and so more infectious.

The more viruses there are circulating in the community the more chances there are of mutations, or variants.

The less Covid around, the less chance of a dangerous variant which is why we need to vaccinate the world.

No one is protected until we’re all protected.

To be more positive, viruses can mutate to become less dangerous.

A virus which allows the sufferer to stay well enough to mix, cough and spread the virus is more successful than one which quickly kills the patient.

In the 1890s there was a 'flu' pandemic which gave very similar symptoms to Covid including a high temperature and loss of smell.

Coronavirus was unknown and it is possible that this pandemic was not influenza but coronavirus.

The theory is that, just like today’s SARS-CoV-2 virus it spread from animals, in this case cows.

If it was a coronavirus it seems to have evolved into a benign form and is probably still around causing today’s minor winter colds.

We do not know whether today’s coronavirus will mutate into a benign form but today we have the huge advantage of a vaccine.

We don’t have to watch as thousands suffer and die before knowing whether the virus will mutate into a harmless form.

From the theories of Charles Darwin we now realise that the evolution of viruses and humans use the same process, natural selection.

Covid is probably descended from a bat virus in China, we are all descended from our African ancestors through numerous mutations.

If any good can come from this awful pandemic perhaps we can all get a better understanding of Charles Darwin’s amazing ideas.